Water pipelines are generally subjected to anomalies such as leakage, bursts and corrosion that can have severe consequences for the environment and the economy. Therefore, in order to ensure the reliability of water pipelines, they must be monitored effectively. Wireless Sensor Networks (WSNs) have emerged as an effective technology for monitoring critical infrastructure such as water, oil and gas pipelines. These WSNs typically employ different type of sensors, such as temperature sensor, pressure sensor, acoustic sensor, flow sensor, and pH sensor for water pipeline monitoring. These sensors generate appropriate electrical signals based on the sensed phenomena. Generally, monitored parameters include temperature, humidity, flow and pressure. Therefore, selecting an appropriate sensor or sensing technique depends on many aspects such as the pipeline material and environment.
In the prior art, the WSNs generally employ a single mobile WSN node that performs the entire monitoring operation of a pipeline. A typical WSN node consists of a sensing subsystem, a processing subsystem, a communication subsystem and a power supply subsystem. The processing subsystem mainly includes a microcontroller and memory processes for storing the sensor data. The WSN node is allowed to move with the water current from the pipeline source down to the pipeline sink where the node is collected and its memory content is copied to a computer. The RF transceiver of the WSN node, which is an important part of communication subsystem receives commands from a central computer and transmits data collected by the static components of the WSN node to the central computer. Moreover, the power for the mobile WSN node is derived from a battery or an energy harvesting (scavenging) device.
Within the pipeline, the mobile WSN node locates measures and logs many events pertaining to the monitoring operation during its long trip within the pipeline. Consequently, the mobile WSN node must be equipped with a large memory size for accommodating the collected information and a long battery life to keep the mobile WSN node alive during its trip through the pipeline.
Moreover, the mobile WSN node must be highly reliable guaranteeing completion of the monitoring operation throughout the entire pipeline distance. In order to achieve this, the mobile WSN node is deployed with a huge physical size at a high cost. The huge size of the mobile WSN node causes the node to get trapped inside the pipeline, thus, blocking the fluid current.
Therefore, in light of the above, there is a need for an improved method and system for monitoring a long-distance pipeline using a plurality of mobile sensor nodes in WSNs.
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